More than once I have wasted my time in attempt to introduce graphics into the webpage, some of these attempts are recorded in this very blog: First were my lines in CSS, followed by rotating rectangles. I say "wasted" because I have now found Raphaël, and I'm in love.

Raphaël

What is it? Their site is too modest, claiming "Raphaël is a small JavaScript library that should simplify your work with vector graphics on the web".
While true, it is also a most ambitious project to change the way the web looks, whether they mean to or not.
All (popular) browsers support vector graphics: IE supports VML, and all other browsers support SVG. By implementing both languages and switching between them, you can create complex vector graphics that work in almost every browser.
This idea was new to me, at least, and I think it's great. Now Raphaël comes along and does it for you. Nice.

My Prophecy
Vector graphics (VG) will become more popular. As VG libraries mature (and Raphaël is already in good shape), VG on the web would become so easy that anyone could use them, and many would. Soon enough you will have beautiful interactive GUIs. At fiirst snippets and demos, then complete libraries for everyone to use. What more can it do? Maybe interactive animations, maybe just add some spice to websites.
It probably won't bury Flash, but I expect it would be a competition.